In typical thin layer or paper chromatographic processes a drop of the solution of chemical compound (s) to be identified is spotted near one end of the chromatography paper, glass plate or plastic film (chromatographic elements) and the end is immersed in an elution solvent (developer) which selectively separates the chemical compounds in the test drop, generally for comparision with known standards or established R.sub.f values of the constituents. Chromatographic elements can and have been developed in chambers ranging from beakers or test tubes or specially designed sandwich type chromatography chambers. However, except for special purpose chromatography chambers, such as for paper partition chromatography, development chambers now available carry out the developing process almost immediately after the chromatographic element is placed therewithin because the liquid solvent almost immediately is brought into contact with the element. It has now been found that solvent development is improved and good resolution, sharp spots and consistent R.sub.f values assured where the chromatographic elements are saturated with the solvent vapor prior to actual development by contact with the liquid solvent.